delphi中怎么在DBgrid中实现鼠标滚轮效果？

delphi中怎么在DBgrid中实现鼠标滚轮效果？

用ADO+DBgrid访问的记录

---

  private
    procedure ApplicationEvents1Message(var Msg: tagMSG;var Handled: Boolean);      //在下面的过程写好后直接按Ctrl+Shift+C将自动生成此段代码
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
//------------------------------------------------------------------------------
procedure  TForm1.ApplicationEvents1Message(var  Msg:  tagMSG;var  Handled:  Boolean);
begin
if  (DBGrid1.Focused)  And  (Msg.message  =  WM_MOUSEWHEEL)  then
      begin
          if  Msg.wParam  >  0  then
              SendMessage(DBGrid1.Handle,  WM_KEYDOWN,  VK_UP,  0)
          else
              SendMessage(DBGrid1.Handle,  WM_KEYDOWN,  VK_DOWN,  0);
          Handled  :=  True;
      end;
if  (DBGrid2.Focused)  And  (Msg.message  =  WM_MOUSEWHEEL)  then